The internet is filled with articles, videos and social media posts about the ketogenic (keto) diet, but this trendy diet has been around in one form or another for nearly 100 years.

Created to help control seizures in children with epilepsy, it became popular in the 1970s when Dr. Robert Atkins introduced his version and its two-week ketogenic phase. Since that time, celebrities and other influencers have flocked to the diet to show off their losses and their latest bacon beauty shot.

“We saw this with gluten-free and celiac a few years back,” says registered dietitian Carla Schuit, MPH, LDN. “And keto is the newest joiner to the club. People who struggle with weight look to find a reason as to why it is difficult. If a diet works for one health condition, why wouldn’t it work for them, too?”

Keep in mind that most people don’t stick to fad diets, especially those that are very restrictive. When they stop the diet, they usually gain back the weight (and then some). Rapid weight loss and regain, or yo-yo dieting, can have long-term negative effects on your health. And it can even make it harder to lose weight on down the line.

What Is the Keto Diet?

What does the ketogenic diet allow you to eat? Instead of breads, pastas and other high carbohydrate foods, the diet is heavy in proteins and fats. Other foods include sausages, eggs, cheeses, avocados, fish, nuts, butter, seeds and fibrous vegetables.

Processed foods, sugar and alcohol are not allowed on the diet.

How Does the Keto Diet Work?

The keto diet works by limiting your carbohydrate intake. As your body runs out of carbohydrates, it compensates by releasing ketones — chemicals made of fat — into your bloodstream.

Once your body reaches this state of ketosis, most cells will burn ketones to generate energy. In simple terms, this means fat becomes your fuel.

Many of those who try the diet will lose weight faster than with some other diets, at least in the short term. But long-term results aren’t any better than other diets. Part of the reason for that may be that most people will find it difficult to stick to such a restrictive diet.

Is It Healthy?

While reducing processed carbs and adding healthy fats in moderation is generally a good idea, this extreme version lacks essential nutrients. It does not provide a balanced diet. And it can be heavy in red meats and other fatty foods as well as foods high in salt, which is not healthy.

And it isn’t safe for those with certain health problems. In particular, those with kidney disease, heart disease and diabetes need to talk with their doctor before trying this diet.

There’s also a risk of sleep problems, kidney stones, constipation and gastric reflux.

When asked about how she keeps her clients from jumping on the latest food bandwagon, Schuit says she encourages them to think carefully.

“How is it achieving its claimed results? If they have done fad diets in the past and weren’t successful, what is different about this diet? Be leery of the snake oil. If it seems too good to be true, it is,” Schuit says. “If we didn’t gain it overnight, it isn’t going to come off overnight.”

Be sure to talk to your doctor before starting any weight loss program.

Get back to basics.

For successful long-term weight management, don’t forget the basics. Eat a healthy, balanced diet, have smaller portions, eat fewer processed foods and empty carbs, and get more exercise. It may not be trendy or super fast, but achieving and maintaining a healthy weight the old-fashioned way is likely the best solution in the long run.

Here today, carb tomorrow: Why don’t fad diets work?

LifeTimes: Is this a new era for fad diets?Schuit: Current diets are going beyond nutrition and food choices to sourcing and ethical issues. We have popularized terms such as “clean eating” or “all natural” that have no real definition. Current fad diets care about what you are eating, but also what you aren’t, and where it is coming from. People are confused on what is good or what is bad. And now there is focus on body composition, with tag lines like, “strong is the new skinny.”

LifeTimes: What makes a diet become popular?Schuit: A new diet may promise quick results without deprivation while playing to the desires and fears of people. And this isn’t just weight. The diet may claim to cure or improve health conditions someone didn’t even know they had. It will usually speak to why other diets do not work and theirs does. Everyone is looking for the next big thing, often because the tried and true methods aren’t all that exciting.

LifeTimes: What are the long-term effects of fad dieting?Schuit: Fad diets often lead to weight cycling, mental fatigue and frustration. Fad diets are typically not sustainable. When someone quits a diet, they may regain their weight and usually more. Feeling defeated, they try another fad diet and the cycle continues.

Our bodies have weight set points that they strive to defend. Repetitive yo-yo dieting can cause metabolic adaptation, making it harder to lose weight over time.

Often, I see folks who have done restrictive dieting having a hard time adding in foods that were forbidden on that diet. Instead, they will over-compensate by eating larger portions of approved foods.

LifeTimes: Will fad diets ever go away?Schuit: I don’t think so. Food has become like fashion. Every year health magazines publish trends and hot new foods or what is the best way to bust belly fat. I think as long as people are looking to lose weight or better their health, there will be someone repackaging a new way to do it.